1. Field
This invention relates to beamforming in wireless communication systems.
2. Description of the Related Technology
A wireless communication network is commonly associated with a telecommunications network where the interconnections among the communication devices are implemented without the use of wires. Wireless telecommunications networks are generally implemented with some type of remote information transmission system that uses electromagnetic waves, such as radio waves, for the carrier and this implementation usually takes place at the physical layer of the network.
A wireless personal area network (WPAN) is one type of wireless network used for communication among a plurality of devices, such as computers, mobile phones, personal digital assistants, printers, digital cameras, televisions, media players, etc. Usually, a WPAN covers a short range up to 10 or 20 meters. A number of standards for such short-range network communications have recently been developed, including, but not limited to, Bluetooth and IEEE 802.15.
In some communications systems, such as a WPAN, beamforming can be used at both the transmitter and the receiver. Antenna arrays are often used at both ends of such systems, and need to be trained before the payload is transmitted. However, antenna training introduces unwanted overhead, as it can be a time-consuming process in which no data of interest, such as audio or video data, is transmitted. It is desirable in any communication system to minimize or reduce the amount of overhead.
Further, as a WPAN involves wireless communication, movement of the devices within the network is not hindered by the connection of wires. However, movement of the devices or changes in the environment may disrupt communications between devices by changing the characteristics of the channel between them. Accordingly, there is a need for a method of maintaining reliable transmission and reception in a wireless network, such as a WPAN, without introducing unsatisfactory amounts of overhead.